Boom-and-bucket paving machine



Aug. 25, 1925. 1,550,748

J. F. ROBB BOOM AND BUCKET PAVING MACHIE Filed om. 25, 1923 s sheets-sheet 1 RTGLE Aug. 25. 192s. Y

J. F. ROBB B00 AND BUQKET PAVING MACHINE Filed Oct. 25, 1923 3 Sheets-Sheet 2.

Aug. 25. 1925. 1,550,748

J. F. ROBE BOOM AND BUCKET PAVING MACHINE Filed Oct. 25 1923 3 Sheets-Sheet 43 Z4@ z5 if n 9.937 ,24 L l d f f" ff f 3f Mb a x 1 "5 Q 4f d AN @aww Patented Aug. 25, 1925.

UNITED STATES PATENT OFFICE.

JOI-IN F. ROBB, 0F CLEVELAND HEIGHTS, OHIO, ASSIGNOR TO KOEIIRING COMPANY, OF MILWAUKEE, WISCONSIN, A CORPORATION.

BOOM-AND-BUCKET PAVING MACHINE.

Application filed October 25, 1923.

.jTo @ZZ 'whom t may concern.'

Be it known that I, JOHN F. ROBE, a citizen of the United States, residing at Cleve- Iland Heights, in the county of Cuyahoga and State of Ohio, have invented certain new and useful Improvements in Boom-and- Bucket Paving Machines, of which the following is a specification.

This invention has to do with machines commonly known today as concrete pavers of the boom and bucket type. Such machines comprise primarily a concrete mixer lhaving an attachment associated therewith in the form of a boom equipped with a bucket for distributing concrete for movement along the boom and discharged at a suitable time in its movement.

Reissue Letters Patent of Koehring No. 13,617 granted September 16, 1913 l and Lichtenberg Patent No. 1,411,217 granted March 28, 1922 typify machines such as above broadly described.

The object of the present invention has been to so design a. boom and bucket paver as to utilize the movement of the boom carrying the bucket in a direction transversely of the road subgrade, with the coincident discharge of the bucket, to cause a spreading action of the bucket in depositing the concrete aggregates upon the said subgrade. In other words, I utilize largely the structure of the said Koehring reissue patent with a longitudinal bucket, combined with mechanism for moving the boom simultaneously with the discharge of the bucket to accomplish a spreading action qui-te similar to that of the Lichtenberg patent which utilizes the movement of the bucket along the boom for effecting the spreading operation, however.

The present invention, therefore, resides in those provisions by which the boom of the 'paver is adapted to be moved in a horizontal plane, or approximately such plane, with a simultaneous discharge action of the bucket so that the spreading of the concrete aggregates may be accomplished in a directions transversely of the road subgrade. The invention further resides in automatic features of the mechanism for moving the boom for the spreading action, enabling the said movement to be initiated when the bucket reaches a certain point in its traverse on the boom, together with means whereby the boom will be restored to its initial po- Seral No. 670,728.

sition from which it starts to perform the bucket discharging and spreading function hereinbefore set forth.

Still another object of the invention has been to produce a mechanism of the class referred to, which may be readily combined with known boom and bucket attachments for concrete pavers of the Koehring type most commonly in use today, without necessitating any particular reorganization of the machinery embodied in the known type of paver above referred to.

l/Vith the fregoing objects in view an understanding of the invention will be had by reference to the following detailed description, in conjunction with the annexed drawings, in which:

Figure 1 is a side view of a concrete paving machine very similar to that of the Lichtenberg patent previously identified, and showing the general features of the present invention as embodied therein.

Figure 2 is a somewhat enlarged view showing the boom swing trip mea-ns intermediate the bucket operating cable and the clutch actuating trip rod.

Figure 3 is a top plan view of certain parts of the mechanism shown in Fig. 1.

Figure t is a horizontal sectional view bringing out more clearly the mounting of the clutch operating main sector lever and the adjacent parts at the inner end of the boom for actuating the boom by a swinging movement.

Figure 5 is a. sectional view taken about on the line 5-5 of Figure 1.

Figure 6 is a similar view taken about en the line 6-6 of Figure 1.

Figure 7 is a perspective view of the boom swing gearing and the automatic boom swing clutch mechanism at the inner end of the boom, showing clearly the operating arrangement and certain manual actuating means.

Figure 8 is a detail perspective view showing the reversing lever and latch mechanism controlling the actuation of the boom when swung automatically, or through manual control under certain conditions.

Figure 9 is a sectional view more clearly showing the inner member of the main clutch lever controlling the boom swing operation.

Figures 10 to 13 inclusive are simple diagrammatic views indicating more fully the action of the clutch throwing cams of the inner bar of the main clutch lever for boom swing control purposes.

It is not believed necessary to describe the boom and bucket attachment specifically since the construction illustrated is very largely that of Lichtenberg Patent No. 1,411,217 heretofore referred to. An understanding of said patent will enable a comprehension of the general operation of the mechanism as shown in Figure 1, which illustrates the end of the concrete mixing drum at A as geared by a shaft B to drive certain clutch means generally designated at C by which the bucket moving cable 1 is operated. riihis cable 1 is connected with the carriage 2 equipped with trolley Wheels 3 so as to operate longitudinally of the boom E, said boom preferably comprising spaced channels suitably fabricated into a unit. The carriage 2 moves back and forth on the boom E and is adapted to strike a knock-out or shifter arm 3 adjacent to the outer end of the boom and pivoted to a bracket thereon. r1`he arm 4 is connected with a pull rod 5 extending longitudinally of the boom between the channels thereof. l/Vhen the knock-out arm is rocked upward a pull is exerted on the rod 5 and said rod actuated certain connections at the inner end of the boom E so as to pull downwards upon a bar 6 and crank lever 7, whereby to operate the clutch mechanism at C to reverse the pull on the cable 1, and thereby reverse the direction of movement of the bucket F and the carriage 2 supporting the said bucket.

There is provided a suitable hand wheel mechanism at 8 for operating` a boom adjusting Cable 9 to raise and lower the boom and hold it at different inclined adjustments as required by conditions of service. At its inner end, as seen perhaps best by Figures 4 and 7, the boom is equipped with a worm gear 10 and said worm gear is engaged by a worm 11 on the worm shaft 12. A. hand wheel 13 is fixed to the shaft 12 to turn the shaft and its worm 11, and in this way the boom E may be swung horizontally by manual power.

Thus far described the mechanism or parts are substantially the same as set forth in Lichtenberg Patent No. 1,411,217. rFhe trip mechanism for dumping the bucket is substantially identical with the mechanism of the patent just mentioned, and the means to close the bucket likewise are the rThe bucket F, however, is disposed so that its doors are arranged longitudinally substantially as found in said reissue Patent No. 13.617, the opening or discharge action of the bucket, however, being like that of Patent No. 1,411,217, except that in the latter the bucket is transverse and in the present case the bucket is longitudinal to the boom.

Referring particularly to Figures 4 and 7 to 13, the improvements of my invention may be set forth in detail. I use a power mechanism for operating the worm shaft 12 to swing the boom horizontally, in addition to the hand wheel 13, which in the use of my invention will be very rarely employed. The power drive mechanism includes a bevel gear 14 on the end of the shaft opposite the wheel 13, and adapted to rotate with the shaft. Adapted to mesh with the gear 14 are the clutch gears 15 and 16 at opposite sides of the axis constituted by the shaft 12. The clutch gears 15 and 16 are loosely mounted upon a drive shaft 17 operated by gearing 18 from a shaft 19 driven by gearing 20 upon a horizontal shaft 21 equipped with a spur gear 22 engaging one of the gear rings on the mixer drum A. Each of the clutch gears 15 and 16 has a clutch 23 for connecting it to turn with the shaft 17. lVhen the gear 15 is clutched to the shaft 17 the intermediate gear 14 of the worm shaft will be driven to turn the said shaft in one direction. lVhen the gear 16, however, is clutched to the shaft 17 and the gear 15 unclutched the worm shaft will be driven in the opposite direction from that just men tioned by the coaction of the gears 14 and 15. The gears 14, 15 and 16 and their clutches 23 may be conventional constructions of such parts well known and in common use today.

lThe means for shifting the clutches 23 is adapted to alternately clutch the gears 15 and 16 to the shaft 17, or maintain the clutch mechanism in neutral position so that neither of the said gears will be driven by the shaft 17 For this purpose l provide shifting yokes 24"L on levers 24 suitably pivoted to any substantial support not shown, the levers 24 being connected together by a link bar 25 so that the operation of the clutches 23 may be simultaneously controlled. One of the levers 24 is a bell crank lever having the arm 24h attached by a link rod 26 to another bell crank lever 27 equipped with the selector arms 28. rFhe arms 28 engage in slots 29 of the selector levers 30 and 31 pivoted on a supporting' shaft 32 and normally loose relatively to the shaft. The hubs of the selector levers 30 and 31 are formed with spaced lugs 33. Intermediate the levers 30 and 31 is a shifting lever 34 having a fork 35, the purpose of which will be later described. However, at the end of the lever 34 mounted on the shaft 32 there is carried the selector latch 35, movable into either of two positions, namely, to engage the lugs 33 of the selector arm 31, or the corresponding lugs of the selector arm 30. Then engaged with either arm it will be observed that the latch 35 may operatively connect the shifting lever 34 to the hub of either of the arms 30 or 31, and if the lever 34 is moved up or down its movement will be transmitted to the clutch levers 24 and the clutches 23 will be operated accordingly as will later be set forth.

Thus far, therefore, it will be understood that I have provided a suitable lever mechanism for the operation of the clutches 23, either one first as desired, according to the adjustment of the latch 35, so that the shaft 12 may be caused to be operated by one of the gears 15 and 16 and the boom thereby swung in the particular direction controlled by the particular gear selected to be actuated first. The arrangement of the levers 23 is such furthermore, that when one of the gears 15 and 16 is clutched to the shaft 17 to turn the worm shaft 12 in one direction, the said gear may be unclutched and its opposing gear clutched to the shaft 17 and the worm shaft turned in the opposite direction. It is in this way that I cause a swinging movement of the boom E in opposite directions.

I prefer to control the swinging movement of the boom automatically, for which purpose I provide, pivoted to the boom E to turn therewith, a sortl of skeleton main clutch control lever designated at 36. This control lever 36 is seen best in Figures 4 and 7 as having the pivoted trunnions 37 above which extends an arm 38. At its free end portion the control lever 36 is equipped with an inner sector member 36il and an outer sector member 36h. The whole control lever may be made in one casting preferably, and will turn with the boom as the latter is moved horizontally. Referring to Figure 2 there will be seen to be located in a position lengthwise of the boom E an operating rod 39 somewhat similar to the rod 5 and arranged slidably on the boom. The rod 39 carries a pivoted trip memberl On the lower run of the cable 1 is provided an adjustable trip member 41 secured to the cable in the proper position by a suitable set screw and adapted to engage with the trip member 40 to slide the rod 39 outwardly on the boom. At its inner end the rod 39 is connected with the arm 38 of the control lever 36. The pivoted trip member 40 is so mounted that when engaged by the trip member 41 there will be caused a shifting of the rod 39 outwards on the boom and a simultaneous lifting of the tail of the member 40, which is virtually a dog, at a certain point near the end of the outward movement of the rod 39 caused by the member 41, the tail of the dog 40 will have lifted by contact with the stationary pin to permit the member 41 to escape so that the parts assume approximately the dotted line positions of Figure 2. By reference to Figures 7 and 9 it will be seen that the inner sector member 36n of the control lever 36 has a centrally located neutralizing clutch shifting cam 42 projecting downwardly therefrom, and near its ends are located clutch engaging cams 43 and 44. Cooperating with the said inner sector member 36a also is a neutralizing and operating device, seen best in Figures 7 and 9 as comprising a yoke member 45, between the upper and lower arms of which the member 36a is received. The yoke member 45 has a stem 46 extending downwardly therefrom and mounted upon the bracket portion 47 of the bracket 48 on which the boom is pivotally supported. Springs 49 above and below the bracket member 47 engage with small abutments 50 on the stem 46 and also above and below the bracket member 47. By the coaction between the springs 49 and the abutments 50 the yoke member 45 is normally maintained in what may be called a neutral control position, that is a position which tends to cause or maintain the clutches 23 in neutral condition wherefore no drive is transmitted to the worm shaft 12 from the shaft 17.

It may now be stated that the shifting lever 34 has its fork 35 engaged with the outer sector member of the clutch control lever 36 and the operation of the lever 34 is caused by pivotal movement of the lever 36.

lith the above construction in view I will now describe the cooperation of the parts in a regular cycle of operation of my mechanism. It being assumed that the parts are substantially in the positions of Figure 1, and that the bucket F has been loaded with concrete aggregates in properly mixed condition, and that the said aggregates are ready for distribution, the operator of the machine will actuate the control lever of the clutch mechanism at C and cause outward travel of the bucket F and carriage 2 on the boom E. As the carriage 2 moves outwards on the boom E the cable 1 causes the trip member 41 to move correspondingly toward the outer end of the boom. At a certain point seen in Figure 2, the member 41 engages the dog 40 and slides the clutch operating rod 39 outwards a short distance. Passing now to Figure 7, the said movement of the rod 39 is transmitted to the control lever 36 to raise the latter pivotally and thus elevate the inner and outer sector members 36a and 361. The raising of the member 36l does not influence the yoke member 45, but the raising of the outer sector member 36b causes an upward movement of the shifting lever 34, assuming that the latchA 35 is in the position of Figure 8, the lever 31 will be rocked and the bell crank lever 27 will likewise be rocked in one direction, pushing on the link 26 and rocking the clutch shifting lever 24 which is of bell crank form. There by the two levers 24 are actuated so that the right hand clutch 23 of Figure 7 is thrown in rendering the gear 16 active to drive the gear 14 and turn the worm shaft 12. The

turning of the worm shaft 12, of course, turns the boom E in substantially a horizontal direction with what is known as its horizontal swinging movement.

It will be borne in mind that the boom E is now swinging toward one side ot the subgrade where the pavement is to be laid. It will also be noted that as soon as the clutch 23 aforesaid has been thrown in the trip member 41 will have escaped the dog l0, incident to 'the progressing outward movement ot the bucket F which is traversing the boom E toward its outer end. Just atter the swinging movement of the boom E is initiated in the above manner thel carriage 2 strikes the rocker arm or lever 3 and reverses the action of the clutch mechanism at C' through the cooperation ot the rod 5 and parts 6 and 7.

The reversing of the movement ot the bucket F in this automatic manner causes a tripping of the dumping mechanism of the bucket in the well known manner set forth in Lichtenberg Patent No. 1,411,217 mentioned above, and in the manner set orth also in Lichtenberg Patent No. 1,141,410 issued J une 1, 1915. The mechanism for this purpose is generally illustrated in the drawings and is well known to those versed in the art of paving machines.

rllheretore, the stage oit the operation of the machine as described is such that the boom E is swinging steadily toward one side of the subgrade and is carrying with it the bucket F in a direction transversely ot the pavement being laid. Furthermore, the bucket is discharging simultaneously with the now Swingin g movement of the boom on account of the reversal ot direction of movement of the bucket.

In practical elt'cct as the reverse movement et the bucket takes a moment and the discharge ot the bucket takes place very quickly, the inward trvel et the bucket on the boom is substantially negligible while it is discharging. In other words,the bucket is practically discharged incident to the swinging moven'ient oit the boom before it obtains any headway, practically speaking, in its movement toward the inner end of the boom. In the meanwhile the boom has now reached its limit ot sidewise movement for its spreading distributing action of the bucket and the cam 13 on the inner sector member strikes the upper part ot the yoke 45, as seen in Figure 11 diagrammatically, and rides under said part ot the yoke 15, as seen in Figure 12 diagraimnatically. This action et the cam causes a lowering ot the control lever 36h below neutral position and correspondingly lowers the` shitting lever 34 and reverses the actuation of the clutch parts, so as to throw in the left hand clutch 23 of Figure 7 and disengage the right hand clutch. Thereby the direction oit driving of the worm shalt 12 is reversed and the swinging movement of the boom is correspondingly reversed, so that the boom begins to turn back to its normal position from which it started, said position according to this mechanism being a central position longitudinally ot the subgrade, although this not being a necessary condition. As the boom is returning to its normal central position the bucket F is returning toward its inner end so as to be ready to receive another batch of aggregates from the drum A. As the boom reaches its original position l'from which it started to swing, the yoke 45 engages with the central neutralizing cam 12 that projects downwardly from the sector member 36u. In this way the yoke l compels an upward movement of the central lever 36 just sufficiently to disengage the lett hand clutch 23 and maintain the two clutches 3 in neutral positions. rl"he boom is thus brought to a stop at its original position 'from which it started to swing, and by this time the bucket may or may not have resumed its normal position adjacent to the mixing drum and cause the neutralization otl the driving clutch mechanism C coacting with the cable 1, which operation is also a known one according to Patent No. 1,411,217.

The control yoke l5 could be rigidly mounted it desired, were its functions restricted to those which I have described. IIowever, I prefer that it be yieldably mounted in accordance with the means previously set lorth, in order that I may attach to the lower end ot the stem 16 an operating lever 51 adapted to be actuated by a rod 52 and manual power applied thereto. Iy operating the rod 52 I can actuate the control lever 3G independently of its operation from the cable trip 41, and throw either clutch 23 into action to cause a swinging of the boom E by the application ot power taken oil oitl the mixing drum or transmitted directly from the engine ot the paver as desired. I note that I may use a rod 53, see Figure 8, to rock the latch 35 in either direction. lVhen the latch is in the position shown in Figure 8, the boom E will be swung from its central position in one direction toward the side of the subgrade, and when the latch is swung to its other position the boom will be swung from its central position toward the other side of the subgrade. I, therefore, obtain a selective control of the direction of movement of the boom from a central point. I wish to say, however, that within the purview of my invention the normal position ot the boom may be extending out with its outer terminal adjacent to a side ot the subgrade, and the swinging movement ot the boom may take it to the opposite side of the subgrade, instead ot the boom working from a central llt) point. Furthermore, instead of having the cams 43 and 44 integral with the inner sector member 36a they might be adjustable so as to control the degree of swing of the boom, in other words, their adjustability would enable the boom to swing properly to adapt its movement for a spreading action of the bucket on roads of different widths.

Summarizing the features of the present machine in the light of its operation, it may be noted that there are provided in combination for the whole general machine, a mechanism to start the swinging of the boom horizontally before the bucket reaches its outer limit of movement; means for causing a discharge action of the bucket after the. movement of the boom has been initiated; an arrangement of doors for the bucket, such that the swinging of the boom will cause the mixed concrete in the bucket to pass therefrom in a stream of suitable thickness, whereby the concrete is laid down on the subgrade in a layer of suflicient thickness to do away with manual spreading as much as possible; means for reversing the swinging movement of the boom to restore it to its normal original position; together with means that reverses the direction of movement of the bucket on the boom at the same time or almost at the same time as the discharging action of the bucket is controlled.

It is to be also noted that my bucket is so carried or mounted upon the boom that its discharge doors will flow the concrete or mixed aggregates to the subgrade in a layer of regulated thickness, sothat the concrete is laid down on the subgrade in layerlike form and transversely of the subgrade to materially reduce the manual spreading of the concrete.

In Figure 10 the inner sector 36a of the control lever 36 is shown in its normal position; in Figure 11 said sector is shifting laterally with the boom as depicted by dotted lines; in Figure 12 the sector has reached its limit of lateral movement and has been caused to throw the boom swinging clutch means into reverse action to reverse the direction of the swinging of the boom, and in Figure 13 the sector is shown as it is about to be raised to its neutral position to neutralize the clutch mechanism and discontinue the swinging o-f the boo-m as the latter reaches its original position.

I may provide a clutch 14a for the gear 14 to connect and disconnect it in relation to the shaft 12, see Fig. 7. When the shaft is to be turned by hand, the gearing 14, 15 and 16 may be disconnected.

I-Iaving thus described my invention what I claim as new and desire to secure by Letters Patent of the United States, is:

1. In a concrete distributing machine in combination, a concrete mixer, a boom and bucket distributing mechanism associated therewith comprising a bucket with a discharge parallel with the boom, means for moving the bucket outwardly and inwardly on the boom, and for discharging said bucket at a desired moment to stream the concrete therefrom in a layer-like form, together with means for swinging the boom simultaneously with the discharge of the bucket whereby the plastic concrete in the bucket is flowed onto the subgrade with a spreading action.

2. In a concrete distributing machine in combination, a concrete mixer, a boom and bucket distributing attachment therefor, comprising a boom, a bucket adapted to traverse the boom and means for discharging the bucket, and means for swinging the boom operated by said mixer.

3. In a concrete distributing machine in combination, a concrete mixer, a boom and bucket distributing attachment therefor comprising a boom, a bucket adapted to traverse the boom and means for discharging the bucket, means for swinging the boom operated by said mixer, and means to render the operation of swinging the boom and discharging the bucket simultaneous.

4. In a concrete distributing machine in combination, a concrete mixer, a boom and bucket distributing mechanism associated therewith, means for moving the bucket outwardly and inwardly on the boom, and for discharging said bucket at a desired moment, together with means for swinging the boo-m simultaneously with the discharge of the bucket, whereby the plastic concrete in the bucket is flowed onto the subgrade with a spreading action, the bucket being equipped with discharging mea-ns to flow the concrete therefrom on a line substantially parallel with the boom.

5. In a concrete distributing machine in combination, a concrete mixer, a boo-m and bucket distributing attachment comprising a boom, a bucket to receive concrete from the mixer and adapted to traverse the boom, means for discharging said bucket automatically at a predetermined point in its movement along the boom, and means for causing a swinging movement of the boom to be initiated just prior to the automatic discharging of the bucket.

6. In a concrete distributing machine in combination, a concrete mixer, a boom and bucket distributing attachment comprising a boom, a'bucket to receive concrete from the mixer and adapted to traverse the boom, means for discharging said bucket automatically at a predetermined point in its movement along the boom, means for causing a swinging movement of the boom to be initiated just prior to the automatic discharging of the bucket, and means for returning the boom to its normal position from which it was swung.

CAQ

7. In a concrete distributing machine in combination, a concrete mixer, a boom and bucket distributing attachment comprising a boom, a bucket to receive concrete from the mixer and adapted to tra-verse the boom, means for discharging said bucket automatically at a predetermined point in its movement along the boom, means for causing a swinging movement of the boom to be initiated just prior to the automatic discharging of the bucket, means ior returning the boom to its normal position from which it was swung, and means for reversing the direction oit movement of the bucket after its discharge operation has been eiiected.

8. A boom and bucket attachment for concrete mixers comprising a boom, a bucket to traverse the boom, cable driving means for the bucket., swinging means tor the boom, and means operated under the control of the cable driving means for initiating the action oitl the boom swinging means.

9. A boom and bucket attachment for concrete mixers comprising a boom, a bucket to traverse the boom, cable driving means for the bucket, swinging means for the boom, means operated under the control of the cable driving means for initiating the action of the boom swinging means, and automatic means 'for reversing the operation of the boom swinging means as initiated `from the cable means.

10. In a boom and bucket attachment for concrete mixers in combination, a boom, a bucket to traverse the same, cable driving means for moving the bucket on the boom, operating` means to swing the boom, a manual controller for said operating` means andautomatic power actuating means for said operating means controllable manually when said controller is used.

11. In a boom and bucket attachment for concrete mixers in combination, a boom, a bucket to traverse the same, cable driving means for moving the bucket on the boom, operating means to swing the boom, a manual controller for said operating means, power actuating means for said operating means, and an automatic device controlling the action of said last mentioned power means to swing the boom independently of the operation of the controller.

12. In a boom and bucket attachment for concrete mixers, in combination a boom, a bucket to traverse the boom, means 'for moving the bucket inward and outward on the boom, and means controlled by the last mentioned means for automatically causing a swinging movement of the boom at a predetermined time.

13. In a boom and bucket attachment for concrete mixers, in combination a boom, a bucket to traverse the boom, means for moving the bucket inward and outward on the boom, means controlled by the last menswinging movement automatically and thereafter discontinuing said swinging' movement.

111. In a boom and bucket attachment for concrete mixers, a boom, a bucket to move thereon, means to carry the bucket inward and outward on the boom, the bucket comprising a` discharge longitudinally of the boom adapted to ilow the plastic concrete therefrom in a layer of predetermined thickness, and means for swinging the hoorn as said bucket is discharged to facilitate a spreading action of the aggregates when laid down on a subgrade as discharged.

15. In a boom and bucket attachment for concrete mixers in combination, a boom, a bucket to traverse the same, worm gearing at the inner end of the boom 'or swinging the same horizontally, means to manually operate said gearing, separate motor driven means for actuating said worm gearing, and automatic means for working the motor driven means aforesaid to swing the boom independently of the operation of the: controller.

16. In a. boom and bucket attachment Jr'or concrete mixers in combination, a boom, a bucket to traverse the same, discharge means for the bucket, and an automatic mechanism comprising a power driven boom swinging device, with means to set it into operation on discharge of the bucket to swing the boom with the bucket, to reverse the swing of the boom, and to then stop the swinging of the boom.

17. In a. boom and bucket attachment for concrete mixers in combination, a boom, a bucket to traverse the boom, cable driving means for said bucket to move it inwardly and outwardly, means to swing the boom horizontally, comprising clutch devices to swing the boom in opposite directions, means adjacent to the outer end of the boom for setting said clutch mechanism into action to swing the boom in one direction and then reverse such swing and stop the swinging, and means on the cable means aforesaid to control the action of the last mentioned means.

18. In a boom and bucket attachment for concrete mixers in combination, a concrete mixer comprising a rotating drum, boom and bucket attachment therefor, comprising a boom, a bucket attached to move inward and outward on the boom, means for swinging the boom horizontally, means for discharging the bucket and means for taking power oil3 of the concrete mixer and applying the same to the boom swinging means for power actuation of the lat-ter.

19. A boom and bucket attachment for concrete mixers comprising a boom, a bucket CIK to traverse the boom, cable driving means for the bucket, swinging means for the boom, means operated under the control of the cable driving means for initiating the action of the boom swinging means, automatic means for reversing the operation of the boom swinging means as initiated from the cable means and for discharging the bucket as the boom swings.

20. In a boom and bucket attachment for concrete mixers, in combination a boom, a bucket to traverse the boom, means for moving the bucket inward and outward on the boom, means controlled by the last mentioned means for automatically causing a swinging movement of the boom at a predetermined time, and in a horizontal direction, and for also dumping the bucket as the boom swings.

21. In a boom and bucket attachment for concrete mixers, in combination a boom, a bucket to traverse the boom, means for moving the bucket inward and outward on the boom, means controlled by the last mentioned means for automatically causing a swinging movement of the boom at a predetermined time, and in a horizontal direction for also dumping the bucket as the boom swings and for restoring the boom to its starting position.

22. In a boom and bucket attachment for concrete mixers, in combination a boom, a bucket to traverse the boom, means for moving the bucket inward and outward on the boom, means controlled by the last mentioned means for automatically causing a swinging movement of the boom at a predetermined time, and in a horizontal direction for also dumping the bucket as the boom swings, and for restoring the boom and bucket to normal positions from which they are operated as above mentioned.

23. In a boom and bucket attachment for concrete mixers, in combination a boom, a bucket to traverse the boom, means for moving the bucket inward and outward on the boom, means controlled by the last mentioned means for automatically causing a swinging movement of the boom at a predetermined time, and in a horizontal direction for also dumping the bucket as the boom swings, and for restoring the boom and bucket to normal positions from which they are operated as above mentioned, automatically acting on said parts.

24. In a concrete distributing machine, in combination, a concrete mixer, a boom and bucket distributing machine associated therewith and comprising a discharge for depositing concrete upon the sub-grade, means for moving the bucket inwardly and outwardly on the boom, and means for automatically and simultaneously swinging the boom and discharging the bucket when the latter reaches a certain point in its movement along the boom, to cause spreading of the concrete when it is deposited on the subgrade below the bucket, as an incident to the said movement of the boom at the same time as the bucket is discharging.

In testimony whereoi` I afiix my signature.

JOHN F. ROBB. 

